From aa4a0729c4e6f94fde5281d6454342bbd4fc69e1 Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.com>
Date: Wed, 19 Jan 2022 17:22:57 +0000
Subject: [PATCH] mfd: simple-mfd-i2c: Add configuration for RPi POE
 HAT

The Raspbery Pi PoE+ HAT exposes a fan controller and power
supply status reporting via a single I2C address.

Create an MFD device that allows loading of the relevant
sub-drivers, with a shared I2C regmap.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
 drivers/mfd/Kconfig          | 10 ++++++++++
 drivers/mfd/simple-mfd-i2c.c | 10 ++++++++++
 2 files changed, 20 insertions(+)

--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -1152,6 +1152,16 @@ config MFD_SY7636A
 	  To enable support for building sub-devices as modules,
 	  choose M here.
 
+config MFD_RASPBERRYPI_POE_HAT
+	tristate "Raspberry Pi PoE HAT MFD"
+	depends on I2C
+	select MFD_SIMPLE_MFD_I2C
+	help
+	  This module supports the PWM fan controller found on the Raspberry Pi
+	  POE and POE+ HAT boards, and the power supply driver on the POE+ HAT.
+	  (Functionally it relies on MFD_SIMPLE_MFD_I2C to provide the framework
+	  that loads the child drivers).
+
 config MFD_RDC321X
 	tristate "RDC R-321x southbridge"
 	select MFD_CORE
--- a/drivers/mfd/simple-mfd-i2c.c
+++ b/drivers/mfd/simple-mfd-i2c.c
@@ -29,6 +29,15 @@ static const struct regmap_config regmap
 	.val_bits = 8,
 };
 
+static const struct regmap_config regmap_config_16r_8v = {
+	.reg_bits = 16,
+	.val_bits = 8,
+};
+
+static const struct simple_mfd_data rpi_poe_core = {
+	.regmap_config = &regmap_config_16r_8v,
+};
+
 static int simple_mfd_i2c_probe(struct i2c_client *i2c)
 {
 	const struct simple_mfd_data *simple_mfd_data;
@@ -75,6 +84,7 @@ static const struct simple_mfd_data sile
 static const struct of_device_id simple_mfd_i2c_of_match[] = {
 	{ .compatible = "kontron,sl28cpld" },
 	{ .compatible = "silergy,sy7636a", .data = &silergy_sy7636a},
+	{ .compatible = "raspberrypi,poe-core", &rpi_poe_core },
 	{}
 };
 MODULE_DEVICE_TABLE(of, simple_mfd_i2c_of_match);
